Azo dyestuffs and their production



Patented Mar. 17, 1936 PATENT OFFICE AZO DYESTUFFS AND THEIR PRODUCTIONHans Krzikalla, Ludwigshafen-on-the-Rhine, and Bernd Eistert, Mannheim,Germany, assignors to General Aniline Works, Inc., New York, N. Y., acorporation of Delaware No Drawing. Original application March 3, 1934,

Serial No. 713,947. Divided and and this application June 14, 1935,Serial No. 26,697. In Germany March 10, 1933 10 Claims.

The present invention relates to new azo dyestuffs and a process ofproducing same. It has been divided out from our copending applicationSer. No. 713,947.

We have found that valuable azo dyestuffs soluble in water are obtainedby coupling diazotized aromatic amines containing at least one sulphonicacid group with compounds containing the ring system i. e. the ringsystem of the so-called pyronone.

Compounds of this kind are for example the 6- alkylor fi-cycloalkylor6-arylor 6-aralkylpyronones, the 5,6-benzoor 5,6-naphtho-condensedpyronones, such as chro'mane-2,4-dione benzochromane-2,4-dione(benzotetronic acid) (naphthotetronic acid) as well as theirsubstitution products, such as alkyl, halogen and nitro derivatives.

The monoazo dyestuffs obtainable from these coupling components with theaid of diazo compounds are usually yellow to red. As diazo compounds maybe mentioned the sul'phonic acids of the diazotized (or tetrazotized)monoand polyamines of the benzine, naphthalene, anthracene, diphenylseries including their ho'mologues and their derivatives, for examplethose substituted by halogen, especially chlorine, nitro, hydroxy,methoxy and carboxylic acid groups; sulphonic acids of diazotizedaminoazo compounds may also be employed. Monodisand poly-azo dyestuffsmay be prepared according to the present invention; in the case ofdisazo dyestufifs one molecule of a suitable tetrazo compound may becoupled with two molecules of equal or different coupling compounds ofthe kind defined abo've or with one molecule of such a compound and onemolecule of any other compound capable of coupling.

On the one hand ready-made dyestuffs may be produced according to thepresent invention by coupling the diazo or tetrazo compounds with thecoupling components. The dyestuffs thus obtainable may be used fordifferent purposes, as 5 for example, for dyeing wool, silk, leather andin some cases cotton.

By employing as diazo components sulphonic acids of ortho-hydroxyorortho-alkoxyamines, yellow to brown dyestuffs are obtained which 10 maybe converted into complex metal compounds by treatment with agentssupplying metals, such as chromium, cobalt or copper compounds, insubstance or on the fibre; in the case of alkoxy compounds the saidtreatment is carried out 15 under conditions under which the alkyl groupis split ofi.

Generally speaking, the dyestuffs have a good fastness to light and aredistinguished by an excellent levelling power and in many cases a goodfastness to washing.

The following examples will further illustrate the nature of thisinvention but the invention is not restricted to these examples. Theparts are by weight.

Example 1 220 parts of 1-methyl-3-amino-6-chlorbenzene-4-sulphonic acidare diazotized in the usual manner and the resulting diazo solution iscoupled with 140 parts of G-methylpyronone (of. Journal of the ChemicalSociety, London, 1891, part I, page 608) dissolved in a sufiicientamount of soda solution. After salting out with common salt, a .yellowdyestuii is obtained which dyes wo'ol beautiful brilliant yellow andvery level shades which are fast to washing and fulling. The resultingdyestuff may be laked in the usual manner, for example, with bariumsalts while 40 adding aluminium sulphate and soda, a beautiful yellowpigment being thus obtained.

Similar dyestufis may be obtained by employing other aromatic aminosulphonic acids or sulphonated aminoazo compounds as diazo components orby using as coupling components benzoor naphthotetronic acid (cf.Annalen der Chemie, vol. 367, pages 196 and 262) or 7,8-benzochromane-2,4-dione (obtainable from 1-hydroxynaphthalene-2-carboxylic acids in a V tainable by condensation of2 molecular proportions of gamma-phenyl acetyl acetic acid ester)Example 2 450 parts of1,4-diamino-3,3'-dimethoxydiphenyl-6,6-disulphonic acid sodium salt aretetrazotized and the resultingtetrazo compound is coupled with 280 partsof .G-methylpyronone in a solution rendered alkaline with soda. Theresulting orange-red disazo dyestufi may be separated by salting outwith common salt and may be employed for dyeing silk.

Example 3 267 parts of l-amino-2-methoxynaphthalenefi-sulphonic acid arediazotized and the resulting diazo compound is coupled with 140 parts of6- methylpyronone in a solution rendered alkaline with soda. Thedyestuff may be separated by salting out and yields orange dyeings onwool.

If the dyestuff be treated in the usual manner with agents sup-plyingchromium, as for example chromium formate, under conditions under whicha splitting off of the methyl radicle takes place, (for example byheating in a closed vessel at between 110 and 130 C.) a dyestuffcontaining chromium is obtained which yields very level Bordeaux reddyeings on Wool.

Example 4 '388 parts of 4,4-diaminodiphenyl-3,3-disulphonic acid sodiumsalt are tetrazotized and coupled with 500 parts of naphthotetronic acidwhile alkaline with soda. The dyestuff dyes cotton orange-red shades.

The dyestuif obtainable in an analogous manner by coupling tetrazotized4,4-diaminostilbene- 3,3'-disulphonic acid with naphthotetronic acidyields at red-brown dyeing on cotton.

Example 7 5 250 parts of the diazo compound of 1-amino-2-hydroxy-naphthalene-4-sulphonic acid are made into a paste with a littleice-cold water and stirred into a solution of 140 parts of6-methylpyronone in 850 parts of pyridine; The whole is stirred at from30 to 40 C. until the coupling is completed and then it is acidifiedwith hydrochloric acid. 7 The resulting dyestufi dyes wool very uniformred-brown shades; the dyeing becomes a fast blue-red by aftertreatmentwith 'bichromate.

The dyestuff may also be converted in substance 'into the complexchromium compound by treatment with chromium formate or the like; thedyestuff is then suitable for dyeing animal fibres.

The dyestuii prepared in a corresponding man- 'ner from the diazocompound of l-amino-Z-hydroxy-fi-nitronaphthalene-4-sulphonic acid andfi-methylpyronone dyes wool very uniform dark brown shades and thechromium compound prepared therefrom in substance or on the fibresyields pale red-brown shades.

Example 6 226 parts of 1-hydroxy-2-amino-4-chlorbenzene-S-sulphonic acidare diazotized and coupled with parts of S-methylpyronone in a solutionrendered. alkaline with soda. The dyestufi dyes wool very uniformyellow-brown shades; the chromium compound prepared by afterchroming onthe fibre or by chroming in substance yields very uniform red-brownshades.

The dyestuff from diazotized l-hydroxy-Z-amino-4-nitrobenzene-6-sulphonic acid and 6- methylpyronone yields veryuniform red-brown shades on wool; its chromium compound yieldsyellow-brown shades.

The dyestufifs may also be employed for dye- 7 ing leather and silk.

Example 7 244 parts of ortho-dianisidine are tetrazotized in the usualmanner with sodium nitrite and hy- Example 8 234 parts of1-amino-2-hydroxy-3-nitrobenzene-5-sulphonic acid are diazotized in theusual manner and allowed to flow into a solution of 2l2 parts ofnaphthotetronicv acid renderedalkaline by means of sodium carbonate,while stirring. A dyestuif is obtained giving level violet shades onwool which upon treatment with bichromate change into a brillantBordeaux.

If the isomeric 1-amino-2-hydroxy-5-nitrobenzene-3-sulphonic acid isused as diazo component a red violet dyestuif is obtained which byafter-chroming yields a beautiful red.

By treating the dyestuffs with agents supplying chromium, for example byheating them for 2 hours with a solution of chromium formate, they maybe converted into dyestuffs contain ingchromium which are suitable fordyeing wool, leather or silk thus yielding shades corresponding to theseobtainable by after-chroming.

What We claim is:

1. The process of producing azo dyestuffs which comprises coupling adiazotized aromatic amine containing at least one sulphonic acid groupwith a compound corresponding to the general formula:

wherein X stands for hydrogen and Y for an alkyl, aryl or aralkyl groupor wherein X and Y are members of an aromatic ring system condensed withthe nucleus shown.

2. The process of producing azo dyestuffs which comprises coupling adiazotized aromatic amine containing at least one sulphonic acid groupwith a compound corresponding to the formula:

wherein X stands for an alkyl, aryl or aralkyl group.

3. The process of producing azo dyestuffs which comprises coupling adiazotized aromatic amine containing at least one sulphonic acid groupwith a compound corresponding to the formula:

4. The process of producing azo dyestuffs which comprises coupling adiazotized aromatic amine containing at least one sulphonic acid groupwith a compound corresponding to the formula:

C '1=o Y 0 wherein the two Ys stand for members of a condensed aromaticring system.

5. The process of producing azo dyestuffs which comprises coupling adiazotized aromatic amine containing at least one sulphonic acid groupwith a compound corresponding to the formula:

6. The process of producing azo dyestuffs which comprises coupling adiazotized aromatic amine containing at least one sulphonic acid groupwith a compound corresponding to the formula:

'7. Azo dyestuffs containing at least one sulphonic acid group derivedfrom a coupling component which corresponds to the general formula:

wherein X stands for hydrogen and Y for an alkyl, aryl or aralkyl groupor wherein X and Y are members of an aromatic ring system condensed withthe nucleus shown.

8. Azo dyestuffs derived from a. diazotized aromatic ortho-hydroxy aminecontaining at least one sulphonic acid group and a coupling componentwhich corresponds to the general formula:

wherein X stands for hydrogen and Y for an alkyl, aryl or aralkyl groupor wherein X and Y are members of an aromatic ring system condensed withthe nucleus shown.

9. Azo dyestuffs containing at least one sulphonic acid group derivedfrom a coupling component which corresponds to the formula:

wherein the two Ys stand for the members of a condensed aromatic ringsystem.

HANS KRZIKALLA. BERND EISTERT.

